Robot assemblies are an important component in automation, especially in manufacturing facilities and manufacturing equipments. For example, in the semiconductor industry, robot arms are used to handle semiconductor wafers, flat panel display, LCD, reticles, masks, or carrier boxes.
In the semiconductor fabrication facility, robot can be used to transport workpieces, typically stored in carrier boxes, from one location to another location, from one equipment to another equipment. In a process system, a robot is typically used to remove the workpieces from the carrier boxes, and then loaded into a loadlock. Another robot can be used to move the workpiece from the loadlock into a processing chamber, and from one processing chamber to another processing chamber. Thus within a processing system, there might be a plurality of robots, each one is designed for a particular task. The processing system could be a deposition system, an etch system, a lithography system, a metrology system, an inspection system, an implantation system, a treatment system, or any workpiece processing system.
Another type of equipment is supplemental equipment such as a stocker, designed for storing the workpieces until needed, or a sorter, designed for sorting the workpieces into certain desirable order. In a typical bare stocker system, a robot is typically used to remove the workpieces from the carrier boxes, and then loaded into a loadlock. Another robot can be used to move the workpiece from the loadlock into a storage chamber, where the workpieces are stored without the original carrier boxes. For box stocker system, the workpieces are stored together with the carrier boxes, without the need for removing them out of the carrier boxes.
Robot handling can be considered overhead operation, since the purpose of robot handling is to transport the workpieces between locations. Thus to improve the efficiency of the fabrication facility and to improve the throughput of the equipment, faster movement of robots, and multiple robot assemblies can be used. Thus some equipments provide a robot assembly with multiple carrier arms, to allow the transfer of multiple workpieces. The multiple carrier arms are typically not independent, and thus maximum efficiency cannot be realized. Another robot configuration includes multiple independent robot arms which can move independently, and thus can essentially double the throughput with one robot. Still another robot configuration includes two separate robots to transport the wafers for an ion implantation system.
Robot is an integral part of many equipments, which provides the most movement within the equipment, thus is prone for failure, especially with the drive for faster robots. The equipment can be down and the facility stops with a simple failure in the robot assembly.